I've noticed some mouthpieces (for example by Theo Wanne and by Johannes 
Gerber) have altered windows - instead of rounded at the bottom of the 
"U", they are nearly squared off.

What noticeable alterations are there in a mouthpieces properties from 
this - if any?

Theoretically at least,  I can see that this would slightly increase the 
effective mouthpiece chamber volume.

Going by a comment by Keith (2007 interview w. Larry Leung) in which 
it's suggested that cheeking out a chamber just beyond the "U" may 
improve a "bratty" lower register in a high baffle mpc, maybe this 
alteration would have some effect on that.

Then there was the extreme case of those mouthpieces with windows 
extending all the way into the table. Never played one, but curious...

Thanks,

Barry




-- 
Barry Levine
10 Hillshire Ln
Norwood MA 02062-3009
781-769-5931

You are correct in your reasoning about longer and squared off window effects.  I hey all make the chamber a little or a lot larger depending on the change.

I would add that undercutting the base of a window makes the mouthpiece blow free-er.  In the case of metal Yana mouthpieces, this is the only change I make if the client likes the tip opening.  The facing is usually very good in these but the "wall" at the bottom of the window is thick.  Undercutting it makes a significant change without doing anything else.  

Making a window much longer has the effect of undercutting as well as making the chamber larger.  It changes how the reed needs to seal on the table and some ligatures might warp a cane reed more than if the table were flat.  

> On Dec 29, 2015, at 7:51 AM, Barry Levine barrylevine@... [MouthpieceWork] <MouthpieceWork@yahoogroups.com> wrote:
> 
> I've noticed some mouthpieces (for example by Theo Wanne and by Johannes 
> Gerber) have altered windows - instead of rounded at the bottom of the 
> "U", they are nearly squared off.
> 
> What noticeable alterations are there in a mouthpieces properties from 
> this - if any?
> 
> Theoretically at least, I can see that this would slightly increase the 
> effective mouthpiece chamber volume.
> 
> Going by a comment by Keith (2007 interview w. Larry Leung) in which 
> it's suggested that cheeking out a chamber just beyond the "U" may 
> improve a "bratty" lower register in a high baffle mpc, maybe this 
> alteration would have some effect on that.
> 
> Then there was the extreme case of those mouthpieces with windows 
> extending all the way into the table. Never played one, but curious...
> 
> Thanks,
> 
> Barry
> 
> -- 
> Barry Levine
> 10 Hillshire Ln
> Norwood MA 02062-3009
> 781-769-5931
> 
>